Needle shield

A method of using a shield for a hypodermic syringe assembly which includes a sheath/needle sub-assembly having a resilient sheath covering the distal portion of a needle cannula, said sheath including a relatively rigid housing forming an elongate chamber therein, the chamber having an open proximal end and a retention means including at least one retention member permanently located within said chamber and away from the chamber open end and formed as a part of the housing, for locking the sheath within the chamber to prevent separation of the sheath from the chamber when the needle cannula is removed, said at least one retention member including a sliding surface and a barbed end, said method of using the shield comprising the steps of:

• inserting the sheath/needle sub-assembly through the open proximal end of the chamber until the sheath engages and slides along the sliding surface of the at least one retention member;
• removing the sheath from the needle cannula by removing the shield while the retention means holds the sheath in locked position therein, the barbed end of the at least one retention member gripping and retaining the sheath against subsequent retraction of the sheath from the chamber.

A method of making a shield for a hypodermic syringe assembly which includes a sheath/needle sub-assembly having a resilient sheath covering a distal portion of a needle cannula, said method of making the shield comprising the steps of:

• forming a relatively rigid housing with an elongate chamber therein, with the chamber being formed with an open proximal end, the open proximal end of the chamber being formed to a size sufficient to allow the sheath/needle sub-assembly to be insertable therethrough into the chamber;
• and
• forming a retention means within the chamber away from the open proximal end for locking the sheath within the chamber when the shield is positioned thereover, said step of forming a retention means includes forming at least one retention member having a sliding surface and a barbed end, said sliding surface of said at least one retention member contacting the sheath during insertion thereof and being relatively resilient when subjected to forces thereagainst caused by the sheath/needle sub-assembly as it is inserted into the shield, and said barbed end of said at least one retention member being relatively rigid when subjected to forces thereagainst caused by the sheath during attempted retraction thereof from the shield, the barbed end functioning to grip and retain the sheath within the chamber.

A shield for insertion over and retention of a sheath of a hypodermic syringe assembly which has been formed by the process of:

• forming a relatively rigid housing having an elongate chamber therein, the chamber being formed with an open proximal end which is sized to allow a sheath/needle sub-assembly of the hypodermic syringe assembly to be insertable therethrough into the chamber;
• and
• forming a retention means within the chamber away from the open proximal end for retaining and locking the sheath within the chamber when the shield is positioned thereover, said step of forming at least one retention including forming a sliding surface and a barbed end on the at least one retention member whereby the sliding surface can contact the sheath during insertion thereof and the barbed end can grip and retain the sheath against subsequent attempts to retract the sheath from the chamber.